Rock-drilling machine.



I No. 892,082.

W. PRELLWITZ. ROCK DRILLNG MACHINE. APPLIGATION FILED APB 17 190e UNITEDsraajns PATENT operon?.

WILLIAMPRELLWITZ, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOI'iL-RANDCOM- PANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

ROCK-DRILLING MACHINE.

Specification of Letters Patent.

Patented .Tune 30, 1908.

Application filed April 17, 1906. Serial No. 312,090.

To alt 'whom it may concern.'

Be it known that I, WILLIAM PRELLWiTz, a citizenof the United States,and resident of Easton, in the county of Northampton and State ofPennsylvania, have invented a new and useful Improvement inRock-Drilling Machines, ofwhich the following is a specification.

lMy invention relates to an improvement in rock drilling machines andhas for its object to provide means for causing an intermittentdischarge of water and air through the drill steel at each stroke of thedrill for thoroughly cleansing the drill hole of the cuttings and alsolaying the dust which arises from the cutting bit of the ,drill steelstriking the rock. Furthermore, the several parts are so constructed andarranged that only a small amount of Water is used for each stroke ofthe drill.-

In the accompanying drawings, Figure 1 is a view partially inlongitudinal central sec-V tion and partially in side elevation of somuch of a rock drilling machine as will give a clear understanding ofthis invention, the drill piston being shown at the limit of itsrearward movement, and Fig. 2 is a similar view with the drill pistonshown at the limit of itsforward movement, the piston alsobeing shownrotated a quarter turn.

The cylinder is denoted by 1 and it is pro- A .vided with the usualpiston chamber 2 and motive fluid ducts 3, 4. The piston head is denotedby 5 and its forwardly extended rod by 6,which rod is provided with achuck 7 at its forward end for the attachment of the hollow drill steel8. The bore of the hollow drill steel 8 is denoted by 9.

Th'e piston rod 6 is provided with a duct 10 therein which, in thepresent instance, is formed by a hole drilled from the front end of theiston rod to a point adjacent to the piston liead. This duct 10 in thepiston rod 6 is provided with a port 11 opening to the periphery of thesaid rod.

The front head is denoted by 12 and may be of any well known andapproved form. This front head is provided with a sleeve 13 whichsu'rroundsV the piston rod 6. This sleeve has its inner wall cut away toform an inner annular space 14 and its outer wall cut away lto form anouter annular space 15. These two spaces are in open communicationthrough holes 16 thereby forming a Water feed chamber. The outer annularspace 15 .comes worn out.

of the water feed chamber is in open communication through ducts 17 witha water inlet pipe 18 connected to any suitable source' of water supplynot shown herein.

' By providing the outer annular space 15 in the sleeve 13, it will beseen that the water feed chamber is always in communication with theducts v17 irrespective of the rotary position in which the sleeve 13 isinserted into its place within the front head. This inlet pipe 18 may beprovided with a cock 19.

The piston rod is packed in the front head against leakage of au'pressure and water, as follows :-The sleeve 13 at its inner end ispacked by two reverse cup-leathers 20 engaging the periphery of thepiston rod 6. The outer end of the sleeve 13 is provided with a U-shapedwasher 21 whereby the inner and outer walls of the sleeve are packed. Astuling box 22 may also be employed in the front head as an additionalsafeguard against the leakage of water around the piston rod.

To prevent the leakage of water at the chuck end of the piston rod, arubber gasket 23 is inserted at the rear of the bushing 24, the openingin the chuck for the gasket 23 being less in diameter than the openingfor the bushing 24, thus leaving ashoulder 25 against which the innerend of the bushing seats.

The inner diameter ofthe gasket 23 is normally less than the outerdiameter of the drill steel sothat when the drill steel is insorted intothe chuck, it will expand the gasket thus making a water-tight joint atthis oint.

, A ole 26 is bored in the chuck opposite the gasket 23 for the purposeof ermltting the withdrawal of the gasket 'wlien it beby pushing thegasket inwardly by a pin inserted intol the hole 26, when the drillsteel is removed and then withdrawing the gasket with a hook insertedinto the end of the chuck.

The duct 1 0 in the piston rod is enlarged at the drill steel seat inthe chuck, as shown at 27, for preventing the duct from becoming closedby the burring over of the mouth of the duct.

The port 11 of the duct 10 in the piston rod is so located that it willbe brought alternately into open communication with the outer and inners ace 15 of the water feed chamber in the ont head and into opencommunication with the piston chamber 2 in front of the piston head 5.As a result of this arrangement it will be seen that when the port l lis in open communication with the water feed chamber in the front head,water will be fed through the duct 10 in the piston rod and the bore 9of the hollow drill steel to the face of the drill.

As the piston head 5 is-moved rearwardly the port 1l is first cut offfrom communication with the water feed chamber in the front head and isthen brought into o en communication with the piston chamllier This willserve to ermit the air to' escape to the face of the dril steel throughthe port l1, duct l0 and bore 9 'thus forcing the water out of the holebeing cut by the drill steel and also thoroughly cleansing the hole ofthe cuttings, the water serving also to lay any dust that the drillsteel may make when striking the rock.

As the port 11 is in communication with the Water feedchamber for asmall portion of each stroke, the amount of water used will be verysmall. It is to be understood that the water may be furnished under thedesired pressure to produce the proper result. It is also to beunderstood that the port 11 is in communication with the piston chamberfor only a small portion of-each stroke as the piston head is near thelimit of its rearward movement.

What I claim is 1. A cylinder, a front head, a hollow drill steel, awater feed'chamber, a separate air lsupply chamber, and a reciprocatingdrill piston having a duct therein vrarranged to be broughtalternatelyinto communication with the water feed chamber and the airsupply chamber for feeding water and air alternately to the drill steel.

2. A cylinder, its piston chamber, a front head, a water feed chambertherein, a hollow drill steel andareciprocating drill iston having aduct therein arranged to lebrought alternately into communication withthe water feed chamber and the piston chamber for feeding water and airalternately to the drill steel. i

3. A cylinder, its piston chamber, a front head, a sleeve therein havinginner and outer connected annular spacesforming a water feed chamber, ahollow drill rsteel and a revdrill piston having a duct therein arrangedto be .broughtA alternately into communication with the water feedchamber and piston chamber for feeding waterand air alternately to thedrill steel, a packing for the pistpn rod at the inner endof the sleeveand a packing for the piston rod and sleeve at the outer end of thesleeve.

5. A hollow drill steel, a piston rod having aduct therein communicatingwith the bore of the drill steel,a chuck for receiving the drill steel,a bushingand a gasket at the inner end of the bushing arranged toencircle the end of the drill steel for forming a water-tight joint atthe drill steel seat, the o ening in the chuck for the gasket being ofess diameter than the o ening for the bushing, thus forming a shou deragainst which the inner end of the bushing seats.'

6. A hollow drill steel, a piston rod having a duct thereincommunicating with the bore ofthe drill steel, a chuck for receiving thedrill steel and a gasket located at they drill steel seat arranged toencircle the end of the drill steel to form a water tight joint,the saidchuck having a transverse hole leading to the gasket for facilitatingits removal from the chuck.

7. A hollow drill steel, a piston ro'd having a duct thereincommunicating with the bore of the drill steel, a chuck for .receivingthe drill steel, a bushing and a gasket located at the inner end of thebushing in position to encircle the end of the drill steel at its seat,said chuck having a transverse hole leading to the gasket forfacilitating the removal of the gasket from the chuck.

In testimony, that I claim the foregoing as my invention, I have signed,my name in presence of two witnesses, this fourteenth day of April1906. y

WILLIAM PRELLWITZ. Witnesses:

WARD RAYMOND, CHASL C. HANSEN.

